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GEOLOGY- Continued,
<br />.ORE BODIES AND ORES.
<br />'; j The large ore shoots, known as the Captain.Sys-
<br />tem, located north of No,E Shaft, may be described ae zones
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<br />~.,I~ of ailioified tuff, full of fractures, the interatines', being
<br />i~ filled with a yellowish or brownish material, consisting prin-
<br />II eipally of the oxides of iron,-manganea~ and tellurium, oarrying
<br />~ high. values in gold, and na doubt having been deposited by mineral
<br />4 j bearing solutions.
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<br />A geologiael freak may be noted in the Anna Lee
<br />j ore shoot, or chimney, said to occupy the pipe, or neck of an
<br />extinct mineral spring, It follows one of the main basalt dykes,
<br />and extends dovrnward, so far as followed, about 1000 feet, It
<br />has several remarkable features, being circular in plan, and vary-
<br />~I ing from 16 to 30 ft, in diameter, and extends nearly vertical,
<br />! but with a sort of cork-screw form into the earth, The ore filling
<br />~~ this pipe, aonsiata of pebbles, well rounded by the action of water
<br />;i and cemented together with material, which is comprised for the
<br />most part, of the same rook, finely pulverized. This ore oontains
<br />?j from 9'fo to 15°fo lime, and 7~O 3ron; thus differing from any other
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<br />ore body of the district. It is also a remarkable feature, that tie
<br />i' gold values aantained in the pebbles and the cementing material, are
<br />about the came, The values are distributed with remarkable even-
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<br />i nesa throughout the mass, dovrn to a point about midway between the
<br />.800 and 900 levels, ( depth about 950 ft, on the shoot, as top of
<br />shoot is 100 ft, above oollar of No,l shaft) where the values dis-
<br />appear, and have failed to come in so far ae explored below, thus
<br />forming a notable exception to the rule of gold deposit a, The
<br />ohimney has been thoroughly explored down to the 900, by sinking
<br />shaft (Anna Lae) down to a depth of 850 ft, to which depth, most
<br />of the materiel has been removed, and by raising from the 900, up
<br />to the bottom of the shaft, The above, with all its available in-
<br />formation, furnishes a queer, and complicated examplo of ore deposition.
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